Currently, development of a solar cell using a substrate comprising a resin, metal foil, or the like as a material has actively been made for the purpose of weight reduction, improving processability, and cost down. As a solar cell that has plasticity and is capable of enduring deformation to some extent, an amorphous silicon solar cell and a CIGS solar cell have become a mainstream of the present time. In addition, vacuum processes such as a plasma CVD method, a sputtering method, and a vapor deposition method have been used for production of solar cells.
Meanwhile, studies on non-vacuum processes have energetically been made. For example, a method for producing a polycrystalline silicon film using a silicon polymer is described in Patent Literature 1. Moreover, studies on a method for producing a CIGS solar cell by a printing method have also been made. In the method, a precursor of copper and indium is printed to form a thin film, and thereafter the solar cell is manufactured through a reduction step and further a selenization step.